I found this to be a fascinating article from the current issue (Oct 2014) of The Atlantic

C-lo
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If life-expectancy trends continue, that future may be near, transforming society in surprising and far-reaching ways.

By Gregg Easterbrook
Photos by Peter Yang
September 17, 2014

For millennia, if not for eons—anthropology continuously pushes backward the time of human origin—life expectancy was short. The few people who grew old were assumed, because of their years, to have won the favor of the gods. The typical person was fortunate to reach 40.

Beginning in the 19th century, that slowly changed. Since 1840, life expectancy at birth has risen about three months with each passing year. In 1840, life expectancy at birth in Sweden, a much-studied nation owing to its record-keeping, was 45 years for women; today it’s 83 years. The United States displays roughly the same trend. When the 20th century began, life expectancy at birth in America was 47 years; now newborns are expected to live 79 years. If about three months continue to be added with each passing year, by the middle of this century, American life expectancy at birth will be 88 years. By the end of the century, it will be 100 years.

Viewed globally, the lengthening of life spans seems independent of any single, specific event. It didn’t accelerate much as antibiotics and vaccines became common. Nor did it retreat much during wars or disease outbreaks. A graph of global life expectancy over time looks like an escalator rising smoothly. The trend holds, in most years, in individual nations rich and poor; the whole world is riding the escalator.

Projections of ever-longer life spans assume no incredible medical discoveries—rather, that the escalator ride simply continues. If anti-aging drugs or genetic therapies are found, the climb could accelerate. Centenarians may become the norm, rather than rarities who generate a headline in the local newspaper.

Pie in the sky? On a verdant hillside in Marin County, California—home to hipsters and towering redwoods, the place to which the Golden Gate Bridge leads—sits the Buck Institute, the first private, independent research facility dedicated to extending the human life span. Since 1999, scientists and postdocs there have studied ways to make organisms live much longer, and with better health, than they naturally would. Already, the institute’s researchers have quintupled the life span of laboratory worms. Most Americans have never heard of the Buck Institute, but someday this place may be very well known.

Buck is not alone in its pursuit. The University of Michigan, the University of Texas, and the University of California at San Francisco are studying ways to slow aging, as is the Mayo Clinic. Late in 2013, Google brought its trove of cash into the game, founding a spin-off called the California Life Company (known as Calico) to specialize in longevity research. Six months after Calico’s charter was announced, Craig Venter, the biotech entrepreneur who in the 1990s conducted a dramatic race against government laboratories to sequence the human genome, also founded a start-up that seeks ways to slow aging.

Should research find a life-span breakthrough, the proportion of the U.S. population that is elderly—fated to rise anyway, considering declining fertility rates, the retirement of the Baby Boomers, and the continuing uplift of the escalator—may climb even more. Longer life has obvious appeal, but it entails societal risks. Politics may come to be dominated by the old, who might vote themselves ever more generous benefits for which the young must pay. Social Security and private pensions could be burdened well beyond what current actuarial tables suggest. If longer life expectancy simply leads to more years in which pensioners are disabled and demand expensive services, health-care costs may balloon as never before, while other social needs go unmet.

With each passing year, the newly born live about three months longer than those born the prior year.

But the story might have a happy ending. If medical interventions to slow aging result in added years of reasonable fitness, life might extend in a sanguine manner, with most men and women living longer in good vigor, and also working longer, keeping pension and health-care subsidies under control. Indeed, the most-exciting work being done in longevity science concerns making the later years vibrant, as opposed to simply adding time at the end.

Postwar medical research has focused on specific conditions: there are heart-disease laboratories, cancer institutes, and so on. Traditional research assumes the chronic later-life diseases that are among the nation’s leading killers—cardiovascular blockage, stroke, Alzheimer’s—arise individually and should be treated individually. What if, instead, aging is the root cause of many chronic diseases, and aging can be slowed? Not just life span but “health span” might increase.

Drugs that lengthen health span are becoming to medical researchers what vaccines and antibiotics were to previous generations in the lab: their grail. If health-span research is successful, pharmaceuticals as remarkable as those earlier generations of drugs may result. In the process, society might learn the answer to an ancient mystery: Given that every cell in a mammal’s body contains the DNA blueprint of a healthy young version of itself, why do we age at all?

Counting yeast

“Here in our freezers we have 100 or so compounds that extend life in invertebrates,” says Gordon Lithgow, a geneticist at the Buck Institute. He walks with me through labs situated on a campus of modernistic buildings that command a dreamlike view of San Pablo Bay, and encourage dreamlike thoughts. The 100 compounds in the freezer? “What we don’t know is if they work in people.”

The Buck Institute bustles with young researchers. Jeans and San Francisco 49ers caps are common sights—this could be a Silicon Valley software start-up were not microscopes, cages, and biological-isolation chambers ubiquitous. The institute is named for Leonard and Beryl Buck, a Marin County couple who left oil stocks to a foundation charged with studying why people age, among other issues. When the institute opened, medical research aimed at slowing aging was viewed as quixotic—the sort of thing washed-up hippies talk about while sipping wine and watching the sunset. A mere 15 years into its existence, the Buck Institute is at the bow wave of biology.

In one lab, researchers laboriously tamper with yeast chromosomes. Yeast is expedient as a research subject because it lives out a lifetime before an analyst’s eyes, and because a third of yeast genes are similar to human genes. Deleting some genes kills yeast; deleting others causes yeast to live longer. Why deleting some genes extends life isn’t known—Buck researchers are trying to figure this out, in the hope that they might then carry the effect over to mammals. The work is painstaking, with four microscopes in use at least 50 hours a week.

Buck employs Lilliputian electrocardiogram machines and toy-size CT scanners to examine the internal organs of mice, since the goal is not just to make them live longer but to keep them healthy longer, with less cancer or heart disease. Researchers curious about aging mainly work with mice, worms, flies, and yeast, because they are small and easily housed, and because they don’t live long, so improvements to life expectancy are quickly observable. “Twenty years ago it was a really big deal to extend the life span of worms. Now any postdoc can do that,” says Simon Melov, a Buck geneticist. Experiments funded by the National Institute on Aging have shown that drugs can extend a mouse’s life span by about a quarter, and Buck researchers have been able to reverse age-related heart dysfunction in the same animal. Think how the world would be upended if human longevity quickly jumped another 25 percent.

The rubber will meet the road with human trials. “We hope to find five to 10 small molecules that extend healthy life span in mice, then stage a human trial,” says Brian Kennedy, the Buck Institute’s CEO. A drug called rapamycin—being tested at the institute and elsewhere—seems closest to trial stage and has revolutionary potential. But in addition to being ethically fraught, human trials of a life-extension substance will be costly, and might take decades. The entry of Google’s billions into the field makes human trials more likely. Calico is tight-lipped about its plans—the company agreed to let me visit, then backed out.